sandbox: keep time offset when resetting

The UEFI Self Certification Test (SCT) checks the SetTime() service with
the following steps:

* set date
* reset
* check date matches

To be compliant the sandbox should keep the offset to the host RTC during
resets. The implementation uses the environment variable
UBOOT_SB_TIME_OFFSET to persist the offset.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 80996a91ce..3d8af0a52b 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -32,6 +32,9 @@
 #include <os.h>
 #include <rtc_def.h>
 
+/* Environment variable for time offset */
+#define ENV_TIME_OFFSET "UBOOT_SB_TIME_OFFSET"
+
 /* Operating System Interface */
 
 struct os_mem_hdr {
@@ -798,6 +801,28 @@ int os_spl_to_uboot(const char *fname)
 	return os_jump_to_file(fname);
 }
 
+long os_get_time_offset(void)
+{
+	const char *offset;
+
+	offset = getenv(ENV_TIME_OFFSET);
+	if (offset)
+		return strtol(offset, NULL, 0);
+	return 0;
+}
+
+void os_set_time_offset(long offset)
+{
+	char buf[21];
+	int ret;
+
+	snprintf(buf, sizeof(buf), "%ld", offset);
+	ret = setenv(ENV_TIME_OFFSET, buf, true);
+	if (ret)
+		printf("Could not set environment variable %s\n",
+		       ENV_TIME_OFFSET);
+}
+
 void os_localtime(struct rtc_time *rt)
 {
 	time_t t = time(NULL);